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171.
Guoqiang Li Tetsuya Kako Zhigang Zou Jinhua Ye 《Journal of solid state chemistry》2007,180(10):2845-2850
A series of orthorhombic photocatalysts (AgNbO3)1−x(NaNbO3)x solid solutions have been synthesized by a solid-state reaction method. The composition dependence of the photophysical and photocatalytic properties of synthesized solid solutions has been investigated systematically. With an increase in the content of NaNbO3, we found that (1) the lattice parameters decreased; (2) the Nb-O bond length in NbO6 octahedron reduced; (3) the band gap increased; and (4) the mean particle size decreased while the Brunauer-Emmett-Teller (BET) surface area increased. Photocatalytic activities of the (AgNbO3)1−x(NaNbO3)x (0?x?0.5) samples were evaluated from gaseous 2-propanol (IPA) decomposition into acetone and CO2 under visible-light irradiation emitted from blue-light-emitting diodes (BLEDs; light intensity: 0.01 mW cm−2). Among all the samples, the (AgNbO3)0.6(NaNbO3)0.4 sample showed the highest photocatalytic activity. 相似文献
172.
Fe3(Co)9(μ3—S)2的P(YR)3(Y=O,S)取代衍生物的合成和结构 总被引:1,自引:0,他引:1
用Fe_3(CO)_9(μ_3-S)_2和P(YR)_3(Y=O,S)在温和条件下反应,获得8种一取代和二取代新的簇合物,发现Fe_3(CO)_9(μ_3-S)_2和P(OR)_3有新的二取代方式,进而合成了另8种具有新的结构的二取代簇合物。对这些簇合物进行了元素分析和IR、~1H NMR、MS表征,并对Fe_3(CO)_7(μ_2-CO)·[P(O-cyclo-C_6H_(11)](μ_3-S)(Ⅷ)进行了X光单晶结构分析。 相似文献
173.
174.
Pb(Ⅱ)与8-羟基喹啉沉淀反应及其分析应用 总被引:1,自引:0,他引:1
研究了在乙酸盐络合保护作用下,8-羟基喹啉与Pb(Ⅱ)沉淀反应条件,测得了8-羟基喹啉铅螯合物的红外光谱图及差热分析数据,结果表明,8-羟基喹啉铅螫合物适合于重量分析,应用于巴氏合金中高含量铅的分析测定,获得了满意的结果。 相似文献
175.
Xiaoning Guo Caihong Hao Guoqiang Jin Huai‐Yong Zhu Xiang‐Yun Guo 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(7):2004-2008
Copper is a low‐cost plasmonic metal. Efficient photocatalysts of copper nanoparticles on graphene support are successfully developed for controllably catalyzing the coupling reactions of aromatic nitro compounds to the corresponding azoxy or azo compounds under visible‐light irradiation. The coupling of nitrobenzene produces azoxybenzene with a yield of 90 % at 60 °C, but azobenzene with a yield of 96 % at 90 °C. When irradiated with natural sunlight (mean light intensity of 0.044 W cm−2) at about 35 °C, 70 % of the nitrobenzene is converted and 57 % of the product is azobenzene. The electrons of the copper nanoparticles gain the energy of the incident light through a localized surface plasmon resonance effect and photoexcitation of the bound electrons. The excited energetic electrons at the surface of the copper nanoparticles facilitate the cleavage of the N O bonds in the aromatic nitro compounds. Hence, the catalyzed coupling reaction can proceed under light irradiation and moderate conditions. This study provides a green photocatalytic route for the production of azo compounds and highlights a potential application for graphene. 相似文献
176.
177.
Zhang Shanyuan Lei Jianping Zhao Longmao Cheng Guoqiang Lu Guoyun 《Acta Mechanica Solida Sinica》2000,13(2):166-172
This article reports an experimental investigation on the axial impact buckling of thin metallic cylindrical shells fully
filled with water. Low velocity impact tests are carried out by DHR-9401 drop hammer rig. The whole process of dynamic buckling
is simulated using LS-DYNA computer code. The consistency between experimental observation and numerical simulation is quite
satisfactory. The investigation indicates that quite high internal hydrodynamic pressure occurs inside the shell during the
impact process. Under the combined action of the high internal pressure and axial compression plastic buckling occurs easily
in the thin-walled shells and buckling modes take on regular and axisymmetric wrinkles.
This project is supported by the National Natural Science Foundation of China(19672039) and the Shanxi Foundation for Returned
Scholars from Abroad. 相似文献
178.
采用偶联剂γ-甲基丙烯酰氧基丙基三甲氧基硅烷(KH570)对纳米氧化钆(nanoGd2O3)表面进行包覆改性, 通过热压成型法制备了一种新型的改性纳米氧化钆/碳化硼/高密度聚乙烯(M-nanoGd2O3/B4C/HDPE)复合材料. 傅里叶变换红外光谱(FTIR)、 扫描电子显微镜(SEM)和X射线能谱(EDS)分析结果表明, nanoGd2O3成功被偶联剂改性, 且改性nanoGd2O3在聚乙烯基体内的界面相容性和分散性显著提高. 热重分析(TGA)、 差示扫描量热分析(DSC)和力学拉伸实验表明, 改性nanoGd2O3的引入增强了复合材料的热稳定性, 提高了复合材料的拉伸强度、 杨氏模量和断裂伸长率. 对复合材料的中子和伽马射线屏蔽性能进行了实验测试和蒙特卡罗模拟计算, 研究了nanoGd2O3改性、 材料形状和材料厚度对屏蔽性能的影响. 结果表明, 界面相容性和分散性优良的nanoGd2O3能够有效提高中子及伽马射线屏蔽率. 方形M-nanoGd2O3/B4C/HDPE材料在厚度为11.7 cm时中子屏蔽率达到90%, 在厚度为13.5 cm时伽马射线屏蔽率达到70%. 相似文献
179.
In situ synchrotron X‐ray diffraction analysis of deformation behaviour in Ti–Ni‐based thin films 下载免费PDF全文
Hong Wang Guangai Sun Xiaolin Wang Bo Chen Xiaotao Zu Yanping Liu Liangbin Li Guoqiang Pan Liusi Sheng Yaoguang Liu Yong Qing Fu 《Journal of synchrotron radiation》2015,22(1):34-41
Deformation mechanisms of as‐deposited and post‐annealed Ti50.2Ni49.6, Ti50.3Ni46.2Cu3.5 and Ti48.5Ni40.8Cu7.5 thin films were investigated using the in situ synchrotron X‐ray diffraction technique. Results showed that initial crystalline phases determined the deformation mechanisms of all the films during tensile loading. For the films dominated by monoclinic martensites (B19′), tensile stress induced the detwinning of 〈011〉 type‐II twins and resulted in the preferred orientations of (002)B19′ parallel to the loading direction (∥ LD) and (020)B19′ perpendicular to the LD (⊥ LD). For the films dominated by austenite (B2), the austenite directly transformed into martensitic variants (B19′) with preferred orientations of (002)B19′ ∥ LD and (020)B19′ ⊥ LD. For the Ti50.3Ni46.2Cu3.5 and Ti48.1Ni40.8Cu7.5 films, martensitic transformation temperatures decreased apparently after post‐annealing because of the large thermal stress generated in the films due to the large differences in thermal expansion coefficients between the film and substrate. 相似文献
180.
Guoqiang Bai Shuanhong Ma Runtian Qie Zhiqing Liu Yulin Shi Cuihua Li Rongjie Wang Xuhong Guo Feng Zhou Xin Jia 《Macromolecular rapid communications》2016,37(15):1256-1261
A facile and versatile approach to constructing colorless surface coatings based on green tea polyphenols is reported, which can further act as a photoinitiating layer to initiate radical polymerization. These colorless green tea polyphenol coatings are capable of successfully photografting polymer brushes, and the resulting polymer brush patterns show spatial shape adjustability by masked UV irradiation. Both surface modifications and photografted polymer brushes do not alter the original color of the substrates. This method could be promising for the development of surface modifications.